Antenna-based qubit annealing method

ABSTRACT

Systems and techniques facilitating antenna-based thermal annealing of qubits are provided. In one example, a radio frequency emitter, transmitter, and/or antenna can be positioned above a superconducting qubit chip having a Josephson junction coupled to a set of one or more capacitor pads. The radio frequency emitter, transmitter, and/or antenna can emit an electromagnetic signal onto the set of one or more capacitor pads. The capacitor pads can function as receiving antennas and therefore receive the electromagnetic signal. Upon receipt of the electromagnetic signal, an alternating current and/or voltage can be induced in the capacitor pads, which current and/or voltage thereby heat the pads and the Josephson junction. The heating of the Josephson junction can change its physical properties, thereby annealing the Josephson junction. In another example, the emitter can direct the electromagnetic signal to avoid unwanted annealing of neighboring qubits on the superconducting qubit chip.

BACKGROUND

The subject disclosure relates to qubit annealing, and morespecifically, to facilitating qubit annealing with antennas. The qubit(e.g., quantum binary digit) is the quantum-mechanical analogue of theclassical bit. Whereas classical bits can take on only one of two basisstates (e.g., 0 or 1), qubits can take on superpositions of those basisstates (e.g., α|0

+β|1

, where α and β are complex scalars such that |α|²+|β|²=1), allowing anumber of qubits to theoretically hold exponentially more informationthan the same number of classical bits. Thus, quantum computers (e.g.,computers that employ qubits instead of solely classical bits) can, intheory, quickly solve problems that would be extremely difficult forclassical computers. The efficacy of quantum computers can be improvedby improving the fabrication and processing of multi-qubit chips. Due tothe phenomenon of frequency collision and/or quantum cross-talk (e.g.,multiple neighboring qubits having too similar resonant frequencies suchthat they have undesired interactions with each other), the ability toprecisely tune and/or alter qubit frequencies is paramount in theconstruction of multi-qubit chips. Traditional solutions for suchfrequency control include tuning of variable-frequency qubits andthermal annealing of fixed-frequency qubits. Variable-frequency qubitshave resonant frequencies that can be tuned by exposure to externalmagnetic fields; however, the additional tuning circuitry required onthe qubit chip adds unnecessary complexity and noise. Thermal annealingof fixed-frequency qubits, which involves heating a qubit so as tochange its physical properties (e.g., resonant frequency), does notintroduce such noise during qubit operation (which is realized atcryogenic temperatures compatible with the superconducting regime).Traditionally, thermal annealing of qubits has been performed by using aphotonic chip with a laser source physically routed to differentlocations on the photonic chip via Mach-Zehnder switches (realized atroom temperature or at temperatures outside the superconducting regime).Although parallel annealing of multiple qubits on a multi-qubit chip ispossible with such a system, the maximum laser power (e.g., and thus themaximum annealing capability) at each location on the photonic chipdepends on the amount of power routed to the other locations on the chip(e.g., if more power from the laser source is routed to location 1, lesspower from the laser source is available to be simultaneously routed tolocation 2). Thus, traditional laser annealing of qubits is best suitedto serial annealing rather than concurrent/parallel annealing of qubits.Therefore, traditional qubit annealing cannot facilitate independentand/or concurrent localized annealing of one or more qubits on amulti-qubit chip.

SUMMARY

The following presents a summary to provide a basic understanding of oneor more embodiments of the invention. This summary is not intended toidentify key or critical elements, or delineate any scope of theparticular embodiments or any scope of the claims. Its sole purpose isto present concepts in a simplified form as a prelude to the moredetailed description that is presented later. In one or more embodimentsdescribed herein, systems, computer-implemented methods, apparatusand/or computer program products that facilitate antenna-based qubitannealing are described.

According to one or more embodiments, a system can comprise asuperconducting qubit chip having a first Josephson junction with afirst set of one or more capacitor pads. The system can also comprise afirst radio frequency (RF) emitter positioned above the superconductingqubit chip. The first RF emitter can emit a first electromagnetic signalonto the first set of one or more capacitor pads. Based on receipt ofthe first electromagnetic signal, the first set of one or more capacitorpads can generate an alternating current or voltage at or within adefined distance from the first Josephson junction. The generatedalternating current or voltage can then anneal the first Josephsonjunction. An advantage provided by these one or more embodiments is thefacilitation of a new technique of thermally annealing one or morequbits (e.g., via antenna-based electromagnetic waves, instead ofphotonic lasers) that leverages the existing quantum circuitry on thesuperconducting qubit chip (e.g., anneals qubits without having tomodify the existing structure/circuitry of the qubit or qubit chip).Optionally, in one or more embodiments, the system can comprise a secondJosephson junction on the superconducting qubit chip with a second setof one or more capacitor pads. In such case, the first RF emitter canlocalize the first electromagnetic signal toward the first set of one ormore capacitor pads of the first Josephson junction to prevent annealingof the second Josephson junction by the first electromagnetic signal. Anadvantage provided by these one or more embodiments is the facilitationof independent qubit annealing (e.g., annealing one qubit on amulti-qubit chip without unwantedly affecting properties of neighboringqubits, such that each of the qubits can achieve various and/or distinctand/or different levels of annealing). In one or more other embodiments,the system can optionally further comprise a second RF emitter. Thesecond RF emitter can emit and localize a second electromagnetic signaltoward the second set of one or more capacitor pads, thereby annealingthe second Josephson junction. Moreover, the second RF emitter can emitand localize the second electromagnetic signal independently of andconcurrently or sequentially with the first RF emitter emitting andlocalizing the first electromagnetic signal, thereby respectivelyfacilitating independent and concurrent or sequential localizedannealing of the first Josephson junction and the second Josephsonjunction. An advantage of these one or more embodiments is to facilitateindependent and/or concurrent/parallel localized annealing of multiplequbits on a multi-qubit chip (e.g., annealing more than one qubit on thesame chip simultaneously and independently, such that each qubit canachieve a distinct level of annealing that can be different from thelevels of annealing of neighboring qubits), thereby expediting theoverall annealing process to save time as compared to serial annealing,as well as improving frequency allocation and reducing quantumcross-talk.

According to one or more embodiments, a computer-implemented method cancomprise emitting, via a first RF emitter, a first electromagneticsignal onto a first set of one or more capacitor pads of a firstJosephson junction of a superconducting qubit chip. The emitting caninduce an alternating current or voltage in the first set of one or morecapacitor pads. The alternating current or voltage can then heat thefirst Josephson junction, thereby annealing the first Josephson junctionbased on the emitting. An advantage of these one or more embodiments isto facilitate a new technique of thermally annealing qubits thatleverages existing quantum circuitry on the superconducting qubit chip(e.g., elimination of need to alter existing quantum circuitry on thesuperconducting qubit chip). Optionally, in one or more embodiments, thecomputer-implemented method can further comprise localizing, by thefirst RF emitter, the first electromagnetic signal toward the first setof one or more capacitor pads of the first Josephson junction. This canprevent annealing of a second Josephson junction on the superconductingqubit chip by the first electromagnetic signal. An advantage of theseone or more embodiments is to facilitate independent annealing ofmultiple qubits (e.g., annealing one qubit on a multi-qubit chip to adefined level of annealing without unwantedly affecting/annealing othernearby qubits on the multi-qubit chip). In one or more otherembodiments, the computer-implemented method can optionally furthercomprise annealing, by a second RF emitter, the second Josephsonjunction by emitting and localizing a second electromagnetic signaltoward a second set of one or more capacitor pads of the secondJosephson junction. Moreover, the emitting and localizing of the secondelectromagnetic signal can occur independently of and concurrently orsequentially with the emitting and localizing of the firstelectromagnetic signal. This can respectively facilitate independent andconcurrent or sequential localized annealing of the first Josephsonjunction and the second Josephson junction. An advantage of these one ormore embodiments is to facilitate independent and concurrent localizedannealing of multiple qubits on a multi-qubit chip (e.g., simultaneouslyannealing more than one qubit on a multi-qubit chip, such that eachqubit on the chip achieves a distinct level of annealing, and such thatthe distinct levels of annealing of the various qubits on the chip canbe different).

According to one or more embodiments, an apparatus can comprise asuperconducting qubit chip having a first qubit with a first set of oneor more capacitor pads and a first Josephson junction. The apparatus canalso comprise a first antenna, located above the superconducting qubitchip. The first antenna can emit a first electromagnetic wave onto thefirst set of one or more capacitor pads. The first electromagnetic wavecan then heat the first qubit, thereby annealing the first Josephsonjunction of the first qubit. An advantage of these one or moreembodiments is to facilitate a new technique of qubit annealing thatmakes use of existing quantum circuitry on a superconducting qubit chip,thereby eliminating the need to retrofit the chip with specializedannealing/tuning circuitry. Optionally, in one or more embodiments, thefirst antenna can adjust at least one of a duration, a frequency, or amagnitude of the first electromagnetic wave to achieve a defined levelof the annealing of the first Josephson junction of the first qubit. Anadvantage of these one or more embodiments is to facilitate independentannealing of a qubit, such that the level of annealing achieved by thequbit can be controlled by controlling/adjusting characteristics of theemitted electromagnetic waves.

According to one or more embodiments, a computer-implemented method cancomprise emitting, via a first antenna, a first electromagnetic waveonto a first set of one or more capacitor pads of a superconductingqubit chip. The first electromagnetic wave can then heat a firstJosephson junction of a first qubit of the superconducting qubit chip,thereby annealing the first Josephson junction of the first qubit basedon the emitting. An advantage of these one or more embodiments is tofacilitate a new technique of qubit annealing that makes use of existingquantum circuitry on a superconducting qubit chip, thereby eliminatingthe need to retrofit the chip with specialized annealing/tuningcircuitry. Optionally, in one or more embodiments, thecomputer-implemented method can further comprise adjusting at least oneof a duration, a frequency, or a magnitude of the first electromagneticwave to achieve a defined level of the annealing of the first Josephsonjunction of the first qubit. An advantage of these one or moreembodiments is to facilitate independent annealing of a qubit, such thatthe level of annealing achieved by the qubit can be controlled bycontrolling/adjusting characteristics of the emitted electromagneticwaves.

According to one or more embodiments, a device can comprise asuperconducting qubit chip having one or more qubits. The device canalso comprise a semiconductor chip having one or more electromagnetictransmitters. The semiconductor chip can be mounted on thesuperconducting qubit chip so that at least one of the one or morequbits has above it a corresponding one of the one or moreelectromagnetic transmitters. The corresponding one of the one or moreelectromagnetic transmitters can then emit a localized electromagneticwave toward a set of one or more capacitor pads of the at least one ofthe one or more qubits. The localized electromagnetic wave can then heatthe at least one of the one or more qubits, thereby annealing aJosephson junction of the at least one of the one or more qubits. Anadvantage of these one or more embodiments is to facilitate independentand concurrent annealing of multiple qubits on a multi-qubit chip.

DESCRIPTION OF THE DRAWINGS

FIGS. 1A and 1B respectively illustrate a top-view schematic and aside-view schematic of an example, non-limiting system that facilitatesantenna-based qubit annealing in accordance with one or more embodimentsdescribed herein.

FIG. 2 illustrates an equivalent circuit diagram of an example,non-limiting system that facilitates antenna-based qubit annealing inaccordance with one or more embodiments described herein.

FIG. 3 illustrates a flow diagram of an example, non-limitingcomputer-implemented method that facilitates antenna-based qubitannealing in accordance with one or more embodiments described herein.

FIG. 4 illustrates a flow diagram of an example, non-limitingcomputer-implemented method that facilitates controlling anelectromagnetic signal to achieve a defined level of antenna-based qubitannealing in accordance with one or more embodiments described herein.

FIG. 5 illustrates a flow diagram of an example, non-limitingcomputer-implemented method that facilitates ceasing to emit anelectromagnetic signal based on achieving a defined level ofantenna-based qubit annealing in accordance with one or more embodimentsdescribed herein.

FIG. 6 illustrates a side-view schematic of an example, non-limitingsystem that facilitates localized antenna-based qubit annealing inaccordance with one or more embodiments described herein.

FIG. 7 illustrates a flow diagram of an example, non-limitingcomputer-implemented method that facilitates localizing antenna-basedqubit annealing in accordance with one or more embodiments describedherein.

FIG. 8 illustrates a side-view schematic of an example, non-limitingsystem that facilitates antenna-based qubit annealing of multiple qubitsin accordance with one or more embodiments described herein.

FIG. 9 illustrates a flow diagram of an example, non-limitingcomputer-implemented method that facilitates annealing multiple qubitsby antenna-based qubit annealing in accordance with one or moreembodiments described herein.

FIG. 10 illustrates a side-view schematic of an example, non-limitingsystem that facilitates antenna-based qubit annealing in accordance withone or more embodiments described herein.

FIG. 11 illustrates a flow diagram of an example, non-limitingcomputer-implemented method that facilitates antenna-based qubitannealing in accordance with one or more embodiments described herein.

FIG. 12 illustrates a flow diagram of an example, non-limitingcomputer-implemented method that facilitates adjusting anelectromagnetic wave to achieve a defined level of antenna-based qubitannealing in accordance with one or more embodiments described herein.

FIG. 13 illustrates a side-view schematic of an example, non-limitingsystem that facilitates directed antenna-based qubit annealing inaccordance with one or more embodiments described herein.

FIG. 14 illustrates a flow diagram of an example, non-limitingcomputer-implemented method that facilitates directing antenna-basedqubit annealing in accordance with one or more embodiments describedherein.

FIG. 15 illustrates a side-view schematic of an example, non-limitingsystem that facilitates annealing multiple qubits by antenna-based qubitannealing in accordance with one or more embodiments described herein.

FIG. 16 illustrates a flow diagram of an example, non-limitingcomputer-implemented method that facilitates annealing multiple qubitsby antenna-based qubit annealing in accordance with one or moreembodiments described herein.

FIG. 17 illustrates a block diagram of an example, non-limitingoperating environment in which one or more embodiments described hereincan be facilitated.

DETAILED DESCRIPTION

The following detailed description is merely illustrative and is notintended to limit embodiments and/or application or uses of embodiments.Furthermore, there is no intention to be bound by any expressed orimplied information presented in the preceding Background or Summarysections, or in the Detailed Description section.

One or more embodiments are now described with reference to thedrawings, wherein like referenced numerals are used to refer to likeelements throughout. In the following description, for purposes ofexplanation, numerous specific details are set forth in order to providea more thorough understanding of the one or more embodiments. It isevident, however, in various cases, that the one or more embodiments canbe practiced without these specific details.

Superconducting qubits offer a promising path toward constructingfully-operational quantum computers. This is because they can exhibitquantum-mechanical behavior (allowing them to be used for quantuminformation processing) at the macroscopic level (allowing them to bedesigned and fabricated by existing integrated circuit technologies).The fundamental building-block of superconducting qubits is theJosephson junction. Josephson junctions can be formed by sandwiching anon-superconducting material between two superconducting materials, andcan be modified by thermal annealing (e.g., heat treating). Theannealing of a qubit (e.g., annealing a qubit's Josephson junction) canchange a transition frequency of the qubit (e.g., a resonant frequencymarking the transition between a qubit's ground state and an excitedstate). Such manipulation of qubit transition frequencies can enableoptimized frequency allocation, thereby minimizing frequency collisionsand/or quantum cross-talk. For example, multiple qubits on a multi-qubitchip can be individually/independently annealed such that each qubit hasa distinct transition frequency from those of its neighboring qubits,thereby decreasing the likelihood of neighboring qubits inappropriatelyresponding to a computational and/or control signal meant to induce aresponse in only a certain qubit. Concurrent and localized annealing ofqubits would thus benefit the operation of multi-qubit chips. However, aproblem in the prior art is that there is no known scalablemethod/system for performing such concurrent and localized qubitannealing to modify qubit frequencies.

Various embodiments of the present invention can provide solutions tothis problem in the art. One or more embodiments described hereininclude systems, computer-implemented methods, apparatus, and/orcomputer program products that facilitate concurrent and localized qubitannealing. More specifically, one or more embodiments pertaining toconcurrent and/or localized qubit-annealing using antennas and/orelectromagnetic emitters are described. For example, in one or moreembodiments, a radio frequency emitter can emit an electromagneticsignal onto a set of one or more capacitor pads of a Josephson junction,wherein the Josephson junction is a component of a qubit on asuperconducting qubit chip. In one or more non-limiting embodiments, theset of one or more capacitor pads of the Josephson junction can be a setof one or more transmon capacitor pads of the Josephson junction (e.g.,pads of a capacitor, which capacitor is coupled in parallel with theJosephson junction). The set of one or more capacitor pads can receivethe electromagnetic signal; that is, each pad can function as areceiving antenna. In one or more non-limiting embodiments, each pad canfunction as a patch antenna on the superconducting qubit chip. Based onreceipt by the set of one or more capacitor pads, the electromagneticsignal can induce an alternating current and/or voltage in the set ofone or more capacitor pads and/or at or within a defined distance fromthe Josephson junction (e.g., in the circuit lines electrically couplingthe pads to the Josephson junction). That is, the electromagnetic signalcan cause electrons in each of the set of one or more capacitor pads tooscillate, thereby creating an alternating current and/or voltageoscillating in the pads themselves, in the circuit lines electricallycoupling the pads to the Josephson junction, and/or at/across theJosephson junction. The oscillation of electrons in the pads and/or thecircuit lines coupling the pads to the junction and/or the junctionitself can heat the Josephson junction. Such heating can affect theproperties of the Josephson junction, thereby modifying a transitionfrequency of the qubit. Thus, localized qubit annealing can be performedwithout having to add and/or subtract circuitry to/from thesuperconducting qubit chip. In one or more other embodiments, multipleelectromagnetic emitters can be implemented concurrently so as toperform localized annealing on multiple qubits simultaneously. Thus,various embodiments of the present invention can address problems in theart by facilitating independent and concurrent localized annealing ofone or more qubits on a multi-qubit chip.

The embodiments described herein relate to systems, computer-implementedmethods, apparatus, and/or computer program products that employ highlytechnical hardware and/or software to technologically solvetechnological problems in the field of qubit annealing (e.g., thermalannealing of qubits).

Specifically, the field of qubit annealing (which is entirely distinctand separate from the field of quantum annealing) suffers from a lack ofscalable and efficient systems and/or computer-implemented methods forindividually, independently, and/or concurrently annealing one or moresuperconducting qubits on a superconducting qubit chip. As describedthoroughly below, one or more embodiments of the present invention canaddress this technical problem by providing a scalable and efficientsystem and/or computer-implemented method that utilizes one or moreelectromagnetic transmitters to excite sets of one or more capacitorpads of one or more superconducting qubits on a superconducting qubitchip. The electromagnetic transmitters can emit electromagneticradiation (e.g. an electromagnetic wave and/or signal) onto thecapacitor pads of a qubit, thereby heating (and therefore annealing) thequbit.

In one or more embodiments, one or more emitters/transmitters cancorrespond in a one-to-one fashion to one or more qubits on thesuperconducting qubit chip, wherein each emitter can be individuallyand/or independently voltage and/or frequency tunable. That is, eachemitter can be controlled so as to manipulate a duration, a frequency,and/or a magnitude of the electromagnetic wave that it can generate.Each wave/signal can then induce a distinct amount of annealing of thequbit onto which it is emitted. So, each qubit can be individuallyand/or independently annealed (e.g., by adjusting the voltage and/orfrequency of its corresponding emitter/antenna) such that it receives aunique and/or defined level of annealing as compared to its neighboringqubits on the superconducting qubit chip. In other words, each of thequbits can achieve a defined level of annealing via the systems and/orcomputer-implemented methods disclosed herein. For example, one or moreembodiments can facilitate annealing a first qubit by a firstelectromagnetic signal for a first time period, and annealing a secondqubit by a second electromagnetic signal for a second time period,wherein the two time periods can be of the same length and/or ofdifferent lengths, and/or wherein the two signals can be of the samefrequencies, wavelengths, and/or magnitudes and/or of differentfrequencies, wavelengths, and/or magnitudes. Moreover, the one or moreemitters can operate concurrently, thereby facilitating independentand/or concurrent localized annealing of the one or more qubits (e.g.,annealing a first qubit for a first time period, and annealing a secondqubit for a second time period, wherein the two time periods can beoverlapping and/or non-overlapping). Such concurrent and localizedannealing addresses problems in the prior art by saving time as comparedto serial annealing and improving operation/functionality of multi-qubitchips by eliminating frequency collisions and/or quantum cross-talk.

Not only can the disclosed systems and/or computer-implemented methodsefficiently and precisely anneal superconducting qubits individually andconcurrently, but they can also do so without having to change, modify,and/or otherwise adapt the quantum circuitry of the qubits and/or thesuperconducting qubit chip. For example, there is no need to physicallysolder, build through manufacturing steps, couple, and/or etch extracapacitors, inductors, resistors, and/or any other circuitry to thequbit to be annealed. Instead, one or more embodiments disclosed hereincan facilitate qubit annealing by leveraging the existing quantumcircuitry on the superconducting qubit chip (e.g., emittingelectromagnetic waves/signals onto existing capacitor pads that arealready coupled to a Josephson junction). Thus, the prior art problem ofhaving to incorporate additional tuning circuitry to tune qubitfrequencies can be eliminated.

The above-mentioned technical improvements, which are more thoroughlydescribed below, are not abstract, are not merely laws of nature ornatural phenomena, and cannot be performed by humans without the use ofspecialized, specific, and concrete hardware and/or software (e.g.,electromagnetic emitters, emitting electromagnetic signals ontocapacitor pads, and so on).

Now, consider the drawings. FIGS. 1A and 1B respectively illustrate atop-view schematic and a side-view schematic of an example, non-limitingsystem that facilitates antenna-based qubit annealing in accordance withone or more embodiments described herein. With reference now to FIGS. 1Aand 1B, there is illustrated an example system 100 that can facilitateantenna-based qubit annealing of qubits on a superconducting qubit chip102. In various embodiments, the system 100 can be used to facilitateantenna-based annealing of qubits/Josephson junctions on thesuperconducting qubit chip 102 regardless of the fabrication stage ofthe qubits/Josephson junctions. That is, in one or more embodiments, thesystem 100 can be an antenna-based qubit annealing system that annealsqubits/Josephson junctions on the superconducting qubit chip 102,wherein the system 100 can be used for post-fabrication,pre-fabrication, and/or mid-fabrication processing/annealing of thequbits/Josephson junctions. For example, the superconducting qubit chip102 can be fully etched/outfitted with qubits, quantum readoutresonators, and/or other quantum circuitry such that the superconductingqubit chip 102 is fully-fabricated and ready to be implemented in aquantum computer once a defined level of annealing is accomplished. Inother embodiments, the qubits/Josephson junctions on the superconductingqubit chip 102 can undergo additional fabrication/processing after beingannealed by the system 100. In still other embodiments, the system 100can be incorporated into a dedicated qubit-production and/orJosephson-junction-production process, wherein the superconducting qubitchip 102 is a dedicated platform/substrate on which one or morequbits/Josephson junctions are constructed, wherein the qubits/Josephsonjunctions are removed from the superconducting qubit chip 102 afterannealing to be incorporated into other quantum computing chips.

In one or more embodiments, the superconducting qubit chip 102 can be aprinted circuit board comprising one or more sheets/layers of conductingmaterial (e.g., such as copper) laminated onto and/or between one ormore sheets/layers of one or more non-conducting substrates. In variousembodiments, any suitable conductors and/or non-conducting substratesknown in the art can be used. In other embodiments, the superconductingqubit chip 102 can be any platform known in the art that is suitable tocarry one or more superconducting qubits. Regardless of itsconstruction, the superconducting qubit chip 102 can have on it one ormore superconducting qubits, with a superconducting qubit comprising atleast one Josephson junction.

As shown in FIG. 1A, the superconducting qubit chip 102 can have on it asuperconducting qubit, wherein the superconducting qubit can comprise aJosephson junction 104 (marked with “X” in the drawings) and a set ofone or more capacitor pads 106. The set of one or more capacitor pads106 can comprise any capacitor pad construction known in the art. TheJosephson junction 104 can be created by coupling two superconductorstogether via a weak link. As mentioned above, this can be accomplishedby sandwiching a thin layer of non-superconducting material between twolayers of superconducting material, wherein the layer ofnon-superconducting material is the weak link (e.g., S-N-S Josephsonjunction). This can also be accomplished by separating thesuperconductors with a thin insulating barrier, wherein the insulatingbarrier is the weak link (e.g., S-I-S Josephson junction). Additionally,this can be accomplished by applying a physical constriction at thepoint of contact between the two superconductors, wherein theconstricted point is the weak link (e.g., S-s-S Josephson junction).Moreover, since the Josephson junction 104 is a macroscopic structure,it can be constructed by known integrated circuit technologies and/ortechniques (e.g., photolithography, deposition, sputtering, evaporation,doping, and so on).

The Josephson junction 104 can exhibit a Cooper-pair quantum tunnelingeffect (e.g., electrons tunneling through the weak link in the absenceof an applied voltage), thereby allowing for the flow of a supercurrent(e.g., electrical current flowing without resistance/dissipation) acrossthe junction at sufficiently low temperatures. This quantum-mechanicalbehavior at the macroscopic level can allow the Josephson junction 104to function as (or as part of) a qubit (e.g., a device that can occupydiscrete/quantized energy states as well as superpositions of thoseenergy states). In one or more embodiments, the Josephson junction 104can be a component of a transmon qubit (e.g., a type of charge qubit),the quantized energy states of which can correspond to integer numbersof Cooper-paired electrons that have crossed the Josephson junction 104and/or are present on a superconducting island formed in part by theJosephson junction 104. In other embodiments, the Josephson junction 104can be a component of other types of qubits, such as a flux qubit (e.g.,the quantized energy states of which can correspond to integer numbersof magnetic flux quanta penetrating a superconducting loop formed inpart by the Josephson junction 104), a phase qubit (e.g., the quantizedenergy states of which can correspond to quantum charge oscillationamplitudes across the Josephson junction 104), and so on. In any case,properties of the Josephson junction 104 can affect the transitionfrequencies between these quantized energy states, and so annealing(e.g., heat treating) of the Josephson junction 104 can be implementedto tune, modify, and/or alter transition frequencies of a qubitcomprising the Josephson junction 104. As mentioned above, such tuning,modification, and/or alteration can be implemented to reduce frequencycollision and/or quantum cross-talk between multiple qubits, therebyimproving the functionality and/or operation of multi-qubit chips.

Now, the drawings depict a transmon qubit design; that is, asuperconducting qubit in which the Josephson junction 104 is coupled inparallel to a capacitor, which has a set of one or more capacitor pads106 (also called “transmon capacitor pads 106,” “capacitor pads 106,”and/or “pads 106”). However, those of skill in the art will appreciatethat one or more embodiments of the invention can incorporate othercapacitor pad configurations (e.g. serial and/or parallel coupling) andnot solely the transmon configuration. Some non-limiting examples ofother qubit designs that can be used with the qubit-annealing system 100include other types of charge qubits, phase qubits, flux qubits,fluxonium qubits, xmon qubits, quantronium qubits, and so on. In otherwords, even though the present disclosure explicitly discusses thedetails of how existing quantum circuitry of a transmon qubit (e.g.,transmon capacitor pads 106) can be leveraged to perform localizedannealing of the transmon qubit, those of skill in the art willappreciate that the systems and/or computer-implemented methodsdescribed herein can be implemented to leverage the existing quantumcircuitry in other qubit designs to similarly facilitate annealing ofthose other qubits. For example, the systems and/or computer-implementedmethods described herein can be implemented in conjunction with any typeof quantum circuitry component, which component can receiveelectromagnetic signals/waves as an antenna, to facilitate qubitannealing.

Moreover, even though FIGS. 1A and 1B depict a qubit having only asingle Josephson junction 104 and a single set of capacitor pads 106,those of skill in the art will understand that a qubit on thesuperconducting qubit chip 102 can comprise any number of Josephsonjunctions 104 and/or any number of capacitor pads 106. Furthermore,although FIGS. 1A and 1B depict only a single superconducting qubit onthe superconducting qubit chip 102, those of skill in the art willappreciate that any number of superconducting qubits can be positionedon the superconducting qubit chip 102. Similarly, those of skill in theart will understand that additional quantum circuitry (e.g., readoutresonators, flux bias lines, and so on) can be incorporated onto thesuperconducting qubit chip 102, wherein such additional quantumcircuitry is conductively, capacitively, and/or inductively coupled tothe Josephson junction 104 and/or the set of one or more capacitor pads106.

In one or more embodiments, the system 100 can optionally include anemitter chip 108 (not depicted in FIG. 1A) and a radio frequency (RF)emitter 110 on the emitter chip 108. The emitter chip 108 can employ aprinted circuit board construction and/or any other computer chipconstruction known in the art such that the RF emitter 110 can beoperably soldered, etched, and/or attached onto the emitter chip 108. Asshown in FIG. 1B, the emitter chip 108 can be positioned above, mountedabove, mounted on, and/or mounted onto the superconducting qubit chip102, such that the RF emitter 110 is above the superconducting qubitchip 102. In one or more other embodiments, the RF emitter 110 can bepositioned directly or substantially directly vertically above theJosephson junction 104 and/or the set of one or more capacitor pads 106(as shown in FIG. 1B). In still other embodiments, the RF emitter 110can be positioned such that it is above the superconducting qubit chip102 and not directly or substantially directly vertically above theJosephson junction 104 and/or the set of one or more capacitor pads 106.

As depicted in FIG. 1B, the RF emitter 110 can emit, generate, localize,and/or direct an electromagnetic signal 112 toward, on, and/or onto theset of one or more capacitor pads 106. In some embodiments, the RFemitter 110 can be a microstrip antenna (e.g., a patch antenna) that canbe etched, soldered, and/or otherwise attached onto the emitter chip108. In one or more other embodiments, the RF emitter 110 can be adipole antenna, a monopole antenna, an array antenna, a loop antenna, anaperture antenna, a horn antenna, a parabolic antenna, a plasma antenna,and so on. In still other embodiments, the RF emitter 110 can be anydevice, antenna, and/or signal generator known in the art and that canpropagate an electromagnetic signal through space/air (and/or otherwiseacross a medium lacking electrical conductors).

In one or more embodiments, the RF emitter 110 can be voltage and/orfrequency tunable. That is, the RF emitter 110 can becontrolled/manipulated (e.g., by controlling/manipulating an inputalternating current and/or voltage that is fed to the RF emitter 110 togenerate the propagating electromagnetic signal 112) so as tocontrol/manipulate the characteristics of the electromagnetic signal112. In some embodiments, the RF emitter 110 can control a duration, afrequency, and/or a magnitude of the electromagnetic signal 112 togenerate a defined level of the annealing of the Josephson junction 104.For example, the input alternating current and/or voltage that is fed tothe RF emitter 110 to generate the propagating electromagnetic signal112 can be ceased (e.g., set to zero) to stop/cease the emitting of theelectromagnetic signal 112. Thus, the RF emitter 110 can control aduration of the electromagnetic signal 112 by ceasing the emitting basedon achieving the defined level of annealing (e.g., ceasing the emittingafter a defined period of time has elapsed from the RF emitter 110beginning to emit the electromagnetic signal 112). As another example,the oscillation frequency of the input alternating current and/orvoltage that is fed to the RF emitter 110 to generate the propagatingelectromagnetic signal 112 can be increased, decreased, and/or otherwisecontrolled in order to increase, decrease, and/or otherwise control afrequency and/or wavelength of the electromagnetic signal 112. Thus, theRF emitter 110 can control a frequency and/or wavelength of theelectromagnetic signal 112 to hasten and/or slow the annealing of theJosephson junction 104. As yet another example, the magnitude of theinput alternating current and/or voltage that is fed to the RF emitter110 to generate the propagating electromagnetic signal 112 can beincreased, decreased, and/or otherwise controlled in order to increase,decrease, and/or otherwise control a magnitude of the electromagneticsignal 112. Thus, the RF emitter 110 can control a magnitude of theelectromagnetic signal 112 to hasten and/or slow the annealing of theJosephson junction 104. In one or more embodiments, the RF emitter 110can comprise one or more voltage-controlled oscillators that can be usedto generate voltage tunable, current tunable, and/or frequency tunablesignals to enable the RF emitter 110 to generate and control theelectromagnetic signal 112. In some embodiments, the electromagneticsignal 112 can belong to the microwave region of the electromagneticspectrum (e.g., have a frequency that is greater than or equal to 300MegaHertz and lower than or equal to 300 GigaHertz). In someembodiments, the electromagnetic signal 112 can have a maximum power of1 Watt to limit possible damage to the junction.

In one or more embodiments, the wavelength of the electromagnetic signal112 can be adjusted (as explained above) to be greater than orapproximately equal to four times a physical dimension of the set ofcapacitor pads 106 (e.g., four times the microstrip transmission lengthof the set of capacitor pads 106 acting as receiving patch antennas).Because the pads 106 can function as receiving patch antennas, they canefficiently receive signals/waves with wavelengths that are four timesas long as the length of a single pad.

Similarly, in one or more embodiments, the RF emitter 110 can be sizedto match the set of one or more capacitor pads 106 of the Josephsonjunction 104. That is, just as the electromagnetic signal 112 can beadjusted so as to be efficiently received by the pads 106, the RFemitter 110 can be sized/adjusted/modified so as to efficiently transmitthe adjusted signal 112. Those of skill in the art will appreciate thatsuch sizing can depend on the type of antenna implemented in the RFemitter 110. For example, if the RF emitter 110 incorporates a patchantenna, the patch antenna can be sized to have a microstriptransmission length that is a quarter of the wavelength of theelectromagnetic signal 112.

In one or more embodiments, the RF emitter 110 can emit/generate theelectromagnetic signal 112 such that the electromagnetic signal 112 issubstantially isotropic (e.g., the electromagnetic signal 112 isradiated with substantially equal strength in every direction, therebyhaving a substantially spherical radiation pattern). In one or moreother embodiments, the RF emitter 110 can emit/generate and/orlocalize/direct the electromagnetic signal 112 such that theelectromagnetic signal 112 is omnidirectional (e.g., the electromagneticsignal 112 is radiated substantially symmetrically with respect to agiven axis, thereby having a substantially torus-like radiationpattern). In still one or more other embodiments, the RF emitter 110 canemit/generate and/or localize/direct the electromagnetic signal 112 suchthat the electromagnetic signal 112 is directional (e.g., theelectromagnetic signal 112 is radiated more strongly in a givendirection than in other directions, thereby having a radiation patternwith at least one main lobe). In any case, the electromagnetic signal112 can be emitted by the RF emitter 110 toward, onto, and/or on the setof one or more capacitor pads 106.

As shown in FIG. 1B, in one or more embodiments, the set of one or morecapacitor pads 106 can receive and/or capture the electromagnetic signal112 as the electromagnetic signal 112 propagates through space/air. Insuch case, each pad of the set of one or more capacitor pads 106 canfunction as a receiving antenna (e.g., a receiving patch antenna) thatresponds to being exposed to the electromagnetic signal 112. Asdescribed below, the reception of the electromagnetic signal 112 by thecapacitor pads 106 can cause annealing of the Josephson junction 104.Although the present disclosure explicitly describes qubit annealing byleveraging existing capacitor pads (e.g., the set of one or morecapacitor pads 106) that are coupled to the qubit (e.g., coupled to theJosephson junction 104), those of skill in the art will appreciate thatany existing circuitry that is on the superconducting qubit chip 102,that is capacitively, conductively, and/or inductively coupled to aJosephson junction, and that can receive electromagnetic radiation,waves, and/or signals propagating through space/air can be leveraged toimplement one or more embodiments of the present invention.

To better understand how the set of one or more capacitor pads 106(and/or any other circuitry on the superconducting qubit chip 102 thatcan receive the electromagnetic signal 112) can facilitate annealing ofthe Josephson junction 104, consider FIG. 2. FIG. 2 illustrates anequivalent circuit diagram of an example, non-limiting system thatfacilitates antenna-based qubit annealing in accordance with one or moreembodiments described herein. With reference now to FIG. 2, there isillustrated an example circuit diagram 200 that shows how the capacitorpads 106 and the Josephson junction 104 respond upon receiving theelectromagnetic signal 112.

First, consider a high-level explanation. As shown, even though thetransmon capacitor pads 106 make up a capacitor that is coupled inparallel to the Josephson junction 104, the separate pads of the set ofone or more capacitor pads 106 (each labeled 106 in FIG. 2) can beconsidered as individually coupled in series (instead of collectively inparallel) with the Josephson junction 104. As mentioned above, each pad106 can function as a receiving antenna, thereby receiving/capturing theelectromagnetic signal 112. Based on receiving the electromagneticsignal 112, the capacitor pads 106 can generate an alternating currentand/or voltage at or within a defined distance from the Josephsonjunction 104 (e.g., in the circuit lines electrically coupling the setof capacitor pads 106 to the Josephson junction 104). The generatedalternating current and/or voltage can then heat the Josephson junction104, thereby annealing the Josephson junction 104.

Now, consider a more detailed explanation. As mentioned above, theindividual pads of the set of capacitor pads 106 can be thought of asbeing individually coupled in series to the Josephson junction 104. Asalso mentioned above, each pad 106 can receive/capture theelectromagnetic signal 112, thereby functioning as a receiving antenna.When exposed to the electromagnetic signal 112, the electrons in each ofthe capacitor pads 106 can begin to oscillate according to thecharacteristics/properties (e.g., frequency, wavelength, amplitude,magnitude, and so on) of the electromagnetic signal 112. Thisoscillation of electrons in the set of capacitor pads 106 cangenerate/induce an alternating current 206 and/or an alternating voltage208 in each pad 106, wherein the alternating current 206 and/or thealternating voltage 208 have substantially the same (and/or related)frequency and/or magnitude as the electromagnetic signal 112. Thus, eachseparate pad 106, based upon excitation by the electromagnetic signal112, can be considered a separate oscillating signal source 202 (e.g.,an alternating current and/or voltage source), wherein each oscillatingsignal source 202 can generate an alternating current 206 and/or analternating voltage 208. Because FIG. 2 depicts two separate pads 106,FIG. 2 depicts two corresponding oscillating signal sources 202, eachone generating an alternating current 206 and/or an alternating voltage208. However, those of skill in the art will appreciate that additionaland/or fewer capacitor pads (and therefore oscillating signal sources)can be incorporated. Overall, the effect of emitting, via the RF emitter110, the electromagnetic signal 112 onto the set of one or morecapacitor pads 106 is to cause each pad 106 to separately replicate (orsubstantially replicate) the electromagnetic signal 112 as analternating current 206 and/or an alternating voltage 208 that flowsthrough the pads 106 themselves and through the circuit lines couplingthe capacitor pads 106 to the Josephson junction 104, rather than aswaves/signals propagating through space/air.

In one or more embodiments, the frequency and/or magnitude of theelectromagnetic wave 112 can be controlled so as to control thefrequency and/or magnitude of the alternating current 206 and/or thealternating voltage 208. In some embodiments, the magnitude of thealternating voltage 208 can be limited to no more than 50 millivolts soas to avoid damaging the Josephson junction 104.

Now, each alternating current 206 and/or alternating voltage 208 isgenerated at a corresponding oscillating signal source 202 (e.g., at acorresponding pad 106) and can run from the corresponding oscillatingsignal source 202 to the Josephson junction 104 through the circuitlines electrically connecting the corresponding oscillating signalsource 202 to the Josephson junction 104. In FIG. 2, “Z” represents theimpedance 204 from each oscillating signal source 202 to the Josephsonjunction 104 (that is, impedance from each pad 106 to the junction 104).In some embodiments, the capacitor pads 106 can be symmetric, and so thetwo impedances 204 can be equal. In such case, the complex formulationof Ohm's law (e.g., V=I*Z) yields that the two alternating currents 206can also be equal, and can add up at the Josephson junction 104 (sincethe two alternating currents 206 run in opposite directions, as shown inFIG. 2). In other embodiments, the pads 106 can be asymmetric, and sothe two impedances 204 can be unequal. In such case, the complexformulation of Ohm's law yields that the two alternating currents 206can also be unequal, and thus can cancel each other slightly at theJosephson junction 104. In either scenario, the alternating currents 206oscillate back and forth through the circuit lines leading from theoscillating signal sources 202 (e.g., from the capacitor pads 106) tothe Josephson junction 104, and such oscillation can continue for aslong as the RF emitter 110 emits the electromagnetic signal 112.

As known from the complex power equation (e.g., P=V*I), the oscillationof the alternating current 206 can dissipate power in the form of heat,thereby heating the circuit lines connecting the oscillating signalsources 202 to the Josephson junction 104. The oscillating signalsources 202 (e.g., the pads 106) can, themselves, also heat up duringthis oscillation. This heating of the capacitor pads 106 and the linescoupling the capacitor pads 106 to the Josephson junction 104 can thenheat the Josephson junction 104 (e.g., via thermal conduction). Suchheating can alter the physical and/or electrical properties of theJosephson junction 104 (e.g., its critical current, its normal stateresistance, and so on), thereby correspondingly altering a transitionfrequency of the qubit comprising the Josephson junction 104. That is,various embodiments of the present invention leverage the existingquantum circuitry on the superconducting qubit chip to anneal qubits,thereby addressing/solving the prior art problem of having toincorporate specialized tuning circuitry onto the superconducting qubitchip to tune qubit frequencies.

The Josephson junction 104 can be heated in this way to achieve adefined and/or desired level of annealing. As one of skill in the artwill understand, the defined level of annealing can be based on adefined and/or desired transition frequency which the Josephson junction104 is to achieve. For example, if the Josephson junction 104 is to havea transition frequency of A, then it must be annealed at B intensity forC amount of time. The duration, frequency, and/or magnitude of theelectromagnetic signal 112 can be controlled/adjusted so as to providethe required B intensity for C amount of time. Furthermore, the level ofannealing performed on the Josephson junction 104 can be monitored bymonitoring the normal state electrical resistance of the Josephsonjunction 104 (e.g., based on the Ambegaokar-Baratoff formula relatingcritical current to normal state resistance). Those of skill in the artwill appreciate that such monitoring can be implemented by systems andmethods known in the art (e.g., via an Ohmmeter, and so on).

As explained, FIG. 2 depicts a circuit diagram 200 that illustrates theelectrical response of the capacitor pads 106 and the Josephson junction104 to the reception of the electromagnetic signal 112. As mentionedabove, although the drawings (including FIG. 2) depict the set of one ormore capacitor pads 106 in a transmon configuration (e.g., pads of acapacitor, which capacitor is coupled in parallel to the Josephsonjunction 104), the systems and/or methods described herein can be usedwith various other electrical components coupled to the Josephsonjunction 104 in lieu of the capacitor pads 106 (e.g., any component thatcan receive the electromagnetic signal 112 to generate an alternatingcurrent 206 and/or alternating voltage 208 can suffice). Those of skillin the art will appreciate that different but analogous circuit diagramscan be created to describe the electrical properties of suchembodiments.

Now, consider FIG. 3. FIG. 3 illustrates a flow diagram of an example,non-limiting computer-implemented method that facilitates antenna-basedqubit annealing in accordance with one or more embodiments describedherein. That is, FIG. 3 depicts a computer-implemented method 300 ofannealing qubits/Josephson junctions that can be facilitated, forexample, by the systems discussed above and/or illustrated in FIGS. 1A,1B, and 2. Those of skill in the art will appreciate, however, thatother systems, devices, and/or apparatus can be used to implement thecomputer-implemented method 300.

At step 302, a first radio frequency (RF) emitter can emit a firstelectromagnetic signal onto a first set of one or more capacitor pads ofa first Josephson junction of a superconducting qubit chip. As explainedabove, the first set of one or more capacitor pads can function asreceiving antennas to capture/receive the first electromagnetic signal.Based on receipt of the first electromagnetic signal by the first set ofone or more capacitor pads, the emitting can induce an alternatingcurrent or voltage in the first set of one or more capacitor pads (e.g.,via exciting the electrons of the first set of one or more capacitorpads). The alternating current or voltage can then dissipate energy inthe form of heat as they oscillate back and forth in the first set ofone or more capacitor pads and in the circuit lines electricallycoupling the first set of one or more capacitor pads to the firstJosephson junction, thereby heating the first Josephson junction (e.g.,via thermal conduction). At step 304, the first RF emitter can annealthe first Josephson junction based on the emitting. For example, thefirst RF emitter can sustain the emitting of the first electromagneticsignal to induce a defined level of heating (and therefore a definedlevel of annealing) of the first Josephson junction. As explained above,such heating of the first Josephson junction can change its properties(e.g., critical current, normal state resistance), thereby changing atransition frequency between a ground state and an excited state of asuperconducting qubit comprising the first Josephson junction.

Again, those of skill in the art will appreciate that thecomputer-implemented method 300 is not limited to being used only inconjunction with transmon capacitor pads. Indeed, those of skill in theart will understand that the first electromagnetic signal can be emittedonto any type of circuitry/component that is coupled to the firstJosephson junction, that can receive the first electromagnetic signal,and that can generate an alternating current and/or voltage based onreceiving the first electromagnetic signal to heat the first Josephsonjunction. Indeed, one or more embodiments of the present invention arenot limited solely to using transmon capacitor pads.

Now, consider FIG. 4. FIG. 4 illustrates a flow diagram of an example,non-limiting computer-implemented method that facilitates controlling anelectromagnetic signal to achieve a defined level of antenna-based qubitannealing in accordance with one or more embodiments described herein.That is, FIG. 4 depicts a computer-implemented method 400 that cancomprise the computer-implemented method 300 of annealingqubits/Josephson junctions and that can further include an additionalstep of controlling the properties of an emitted electromagnetic signalto correspondingly control the annealing of a targeted Josephsonjunction.

At step 302, as explained above, a first radio frequency (RF) emittercan emit a first electromagnetic signal onto a first set of one or morecapacitor pads of a first Josephson junction of a superconducting qubitchip, wherein the emitting can induce an alternating current or voltagein the first set of one or more capacitor pads, thereby heating thefirst Josephson junction. At step 304, also as explained above, thefirst RF emitter can anneal the first Josephson junction based on theemitting.

Now, at step 402, the first RF emitter can control at least one of aduration, a frequency, or a magnitude of the first electromagneticsignal to generate a defined level of the annealing of the firstJosephson junction. Such a step can be implemented by a first RF emitterthat is voltage and/or frequency tunable. That is, the output of thefirst RF emitter (e.g., the first electromagnetic signal) can becontrolled/manipulated by controlling/manipulating an input of the firstRF emitter (e.g., an input electronic signal and/or input alternatingcurrent/voltage). For example, in one or more embodiments, the first RFemitter can function like a transmission antenna known in the art, whichradiates electromagnetic waves based on receiving an alternatingcurrent/voltage at its input terminals. Moreover, the input alternatingcurrent/voltage and the first electromagnetic signal can have the sameand/or substantially related frequencies and/or magnitudes. Thus, bycontrolling the properties of the input alternating current/voltage, theproperties of the first electromagnetic signal generated by the first RFemitter can correspondingly be controlled.

So, for example, ceasing to create and feed the input alternatingcurrent/voltage to the first RF emitter can cease the emission of thefirst electromagnetic signal. This, in turn, can allow for the durationof the first electromagnetic signal to be controlled (e.g., ceasing toemit the first electromagnetic signal once a defined amount of time haselapsed since the emitting began, wherein the defined amount of time canbe an amount of time required to achieve a defined level of annealing ata certain magnitude and/or frequency). As another example, modulating afrequency of the input alternating current/voltage can correspondinglymodulate a frequency of the first electromagnetic signal (e.g., sincethe input alternating current/voltage and the first electromagneticsignal can have the same and/or substantially related frequencies).This, in turn, can allow for the frequency of the first electromagneticsignal to be controlled so as to hasten, slow, and/or otherwisemanipulate the rate and/or extent of annealing of the first Josephsonjunction. As yet another example, modulating a magnitude (e.g., absolutevalue of amplitude) of the input alternating current/voltage cancorrespondingly modulate a magnitude of the first electromagnetic signal(e.g., since the input alternating current/voltage and the firstelectromagnetic signal can have the same and/or substantially relatedmagnitudes). This, in turn, can allow for the magnitude of the firstelectromagnetic signal to be controlled so as to hasten, slow, and/orotherwise manipulate the rate and/or extent of annealing of the firstJosephson junction.

In one or more embodiments, the input alternating current/voltage of thefirst RF emitter can be created and fed to the first RF emitter bysystems/methods known in the art (e.g., by a voltage-controlledoscillator, and so on). In some embodiments, the first electromagneticsignal can belong to the microwave region of the electromagneticspectrum (e.g., can have a frequency that is greater than or equal to300 MegaHertz and lower than or equal to 300 GigaHertz). In someembodiments, the first electromagnetic signal can have a maximum powerof 1 Watt to limit possible damage to the junction.

Now, consider FIG. 5. FIG. 5 illustrates a flow diagram of an example,non-limiting computer-implemented method that facilitates ceasing toemit an electromagnetic signal based on achieving a defined level ofantenna-based qubit annealing in accordance with one or more embodimentsdescribed herein. That is, FIG. 5 depicts a computer-implemented method500 that can comprise the computer-implemented method 400 and that canfurther include an additional step of ceasing to emit an electromagneticsignal once annealing of a Josephson junction is complete.

The first three steps can be as described above. At step 302, a firstradio frequency (RF) emitter can emit a first electromagnetic signalonto a first set of one or more capacitor pads of a first Josephsonjunction of a superconducting qubit chip, wherein the emitting inducesan alternating current or voltage in the first set of one or morecapacitor pads, thereby heating the first Josephson junction. At step304, the first RF emitter can anneal the first Josephson junction basedon the emitting. At step 402, the first RF emitter can control at leastone of a duration, a frequency, or a magnitude of the firstelectromagnetic signal to generate a defined level of the annealing ofthe first Josephson junction.

Now, at step 502, the first RF emitter can cease to emit the firstelectromagnetic signal based on (and/or in response to) achieving thedefined level of the annealing of the first Josephson junction. That is,once the first Josephson junction has been sufficiently annealed, thefirst RF emitter can stop emitting the first electromagnetic signal (asdescribed above), thereby preventing further annealing of the firstJosephson junction. The defined level of annealing (e.g., the amount ofannealing required) can depend on industrial context and/or applicablecircumstances. Moreover, and as mentioned above, the level of annealingof the first Josephson junction can be monitored by monitoring thenormal state resistance of the first Josephson junction (e.g., via anOhmmeter).

Now, consider FIG. 6. FIG. 6 illustrates a side-view schematic of anexample, non-limiting system that facilitates localized antenna-basedqubit annealing in accordance with one or more embodiments describedherein. As shown, the qubit annealing system 600 can comprise thesuperconducting qubit chip 102, the Josephson junction 104, the firstset of one or more capacitor pads 106, the emitter chip 108, and the RFemitter 110 which can emit/generate the electromagnetic signal 112 (alsoreferred to as electromagnetic wave 112), substantially as describedabove.

As shown, the qubit annealing system 600 can further comprise a secondJosephson junction 602 on the superconducting qubit chip 102 and havinga second set of one or more capacitor pads 604. Moreover, the RF emitter110 can localize/direct the electromagnetic signal 112 toward/on/ontothe set of capacitor pads 106 and away from the second set of capacitorpads 604 to prevent annealing of the second Josephson junction 602 bythe electromagnetic signal 112. In other words, due to thelocalizing/directing, the electromagnetic signal 112 can be received bythe set of one or more capacitor pads 106 and not by the second set ofone or more capacitor pads 604, thereby annealing the Josephson junction104 and not annealing the second Josephson junction 602. Thus, theJosephson junction 104 can be independently annealed without causingunwanted annealing of the second Josephson junction 602 and/or otherneighboring Josephson junctions on the superconducting qubit chip 102.An advantage of these one or more embodiments is the facilitation ofindependent and/or localized annealing of qubits (e.g., altering onequbit without altering neighboring qubits), thereby enabling optimalfrequency allocation and reducing frequency collisions and/or quantumcross-talk.

In one or more embodiments, the RF emitter 110 can be a directionalantenna/transmitter as known in the art such that it can localize/directthe electromagnetic signal 112 more strongly in a particular direction(e.g., toward the set of pads 106) than in other directions. Forexample, the RF emitter 110 can comprise an aperture antenna, aparabolic antenna, a helical antenna, a Yagi antenna, a horned antenna,a phase antenna array, and so on.

In one or more embodiments, the RF emitter 110 can be outfitted withelectronic actuators so as to swivel, rotate, and/or otherwise changedirections/orientations such that it can localize/direct theelectromagnetic signal 112 away from the set of pads 106 andtoward/on/onto the second set of pads 604, thereby annealing the secondJosephson junction 602 without further annealing the Josephson junction104. Again, this enables multiple qubits on a multi-qubit chip toundergo independent and localized annealing, such that each qubit canreceive its required level of annealing without unwantedly affecting theannealing levels of neighboring qubits. This can help to facilitateoptimal frequency allocation, thereby reducing quantum cross-talk.

Now, consider FIG. 7. FIG. 7 illustrates a flow diagram of an example,non-limiting computer-implemented method that facilitates localizingantenna-based qubit annealing in accordance with one or more embodimentsdescribed herein. That is, FIG. 7 depicts a computer-implemented method700 that can comprise the computer-implemented method 300 and that canfurther include a step for localizing an electromagnetic signal towardone set of capacitor pads and away from another set.

At step 302, a first radio frequency (RF) emitter can emit a firstelectromagnetic signal onto a first set of one or more capacitor pads ofa first Josephson junction of a superconducting qubit chip, wherein theemitting induces an alternating current or voltage in the first set ofone or more capacitor pads, thereby heating the first Josephsonjunction. At step 304, the first RF emitter can anneal the firstJosephson junction based on the emitting.

Now, at step 702, the first RF emitter can localize the firstelectromagnetic signal toward the first set of one or more capacitorpads of the first Josephson junction to prevent annealing of a secondJosephson junction on the superconducting qubit chip by the firstelectromagnetic signal. As described above in conjunction with FIG. 6,this can enable each qubit on a multi-qubit chip to be individuallyannealed, wherein such individual annealing does not substantiallyaffect, and is not substantially affected by, individual annealing ofneighboring qubits on the multi-qubit chip. Again, an advantage of theseone or more embodiments is the facilitation of independent and localizedannealing of multiple qubits on a superconducting qubit chip (e.g.,affecting desired qubits on the chip without accidentally affectingneighboring qubits on the chip), thereby improving frequency allocationand reducing the likelihood of frequency collisions and/or quantumcross-talk. Such localizing/directing can be accomplished byincorporating a directional antenna into the first RF emitter (e.g., anaperture antenna, a parabolic antenna, a helical antenna, a Yagiantenna, a horned antenna, a phase antenna array, and so on).

Now, consider FIG. 8. FIG. 8 illustrates a side-view schematic of anexample, non-limiting system that facilitates antenna-based qubitannealing of multiple qubits in accordance with one or more embodimentsdescribed herein. As shown, the qubit annealing system 800 can comprisethe superconducting qubit chip 102, the Josephson junction 104, the setof one or more capacitor pads 106, the emitter chip 108, the RF emitter110 which can emit/generate and/or localize/direct the electromagneticsignal 112, and the second Josephson junction 602 having the second setof one or more capacitor pads 604, substantially as described above.

As shown, the qubit annealing system 800 can also comprise a second RFemitter 802 on the emitter chip 108 and/or otherwise positioned abovethe superconducting qubit chip 102. The second RF emitter canemit/generate and localize/direct a second electromagnetic signal 804toward/on/onto the second set of one or more capacitor pads 604, therebyannealing the second Josephson junction 602. Additionally, the second RFemitter 802 can emit/generate and localize/direct the secondelectromagnetic signal 804 independently of and concurrently orsequentially with the RF emitter 110 emitting and localizing theelectromagnetic signal 112, thereby respectively facilitatingindependent and concurrent or sequential localized annealing of theJosephson junction 104 and the second Josephson junction 602. Becausethe electromagnetic signal 112 and the second electromagnetic signal 804can each be independently localized/directed by their respective RFemitters, they can propagate through space/air and/or be received bytheir respective target qubits/capacitor pads without substantiallyinterfering with each other. In other words, the electromagnetic signal112 can propagate so as to not anneal the second Josephson junction 602,and the second electromagnetic signal 804 can propagate so as to notanneal the Josephson junction 104. Moreover, not only can the Josephsonjunction 104 and the second Josephson junction 602 be independentlyannealed via localized emission of the electromagnetic signals 112 and804 (such that the two Josephson junctions 104 and 602 can achievedistinct and/or different levels of annealing, and such that theannealing of one junction does not affect the annealing of the other),but they can also be annealed simultaneously/concurrently, therebysaving time and constituting a significant advantage over serialannealing.

Additionally, as shown in FIG. 8, the RF emitter 110 can be positionedabove the set of one or more capacitor pads 106 of the Josephsonjunction 104 and the second RF emitter 802 can be positioned above thesecond set of one or more capacitor pads 604 of the second Josephsonjunction 602. This can help to localize/direct the electromagneticsignals 112 and 804 such that they are received only by theirrespectively targeted Josephson junctions (e.g., signal 112 received bypads 106 of Josephson junction 104 and not by pads 604 of junction 602;signal 804 received by pads 604 of junction 602 and not by pads 106 ofJosephson junction 104). As used herein, electromagnetic signal 804 maybe referred to as electromagnetic wave 804.

In one or more embodiments, the qubit annealing system 800 can begeneralized to describe parallel/concurrent annealing of multiple qubitson a multi-qubit chip. For example, the generalized system can comprisea superconducting qubit chip (e.g., 102) having one or more qubits(e.g., 104 and 602). Moreover, the generalized system can comprise asemiconductor chip (e.g., 108) having one or more electromagnetictransmitters (e.g., 110 and 802). Furthermore, the semiconductor chipcan be mounted on the superconducting qubit chip (e.g., the emitter chip108 is mounted above the superconducting qubit chip 102) so that atleast one of the one or more qubits has above it a corresponding one ofthe one or more electromagnetic transmitters (e.g., RF emitter 110 canbe directly above Josephson junction 104). The corresponding one of theone or more electromagnetic transmitters (e.g., 110) can emit alocalized electromagnetic wave (e.g. 112) toward a set of one or morecapacitor pads (e.g., 106) of the at least one of the one or more qubits(e.g., 104), thereby annealing a Josephson junction of the at least oneof the one or more qubits (e.g., 104). Again, an advantage of these oneor more embodiments is the facilitation of concurrent and independentannealing of multiple qubits on a multi-qubit chip (e.g., simultaneouslyannealing two qubits to two distinct and/or different levels ofannealing).

In one or more embodiments, the generalized system can comprise at leasttwo of the one or more electromagnetic transmitters (e.g., 110 and 802)that can concurrently or sequentially emit at least two electromagneticwaves (e.g., 112 and 804) toward at least two of the one or more qubits(e.g., 104 and 602). Moreover, the at least two of the one or moreelectromagnetic transmitters (e.g., 110 and 802) can independentlycontrol at least one of a duration, a frequency, or a magnitude (asdescribed above) of the at least two electromagnetic waves (112 and 804)to achieve a defined level of annealing of the at least two of the oneor more qubits (e.g., 104 and 602). That is, in some embodiments, aduration, a frequency, and/or a magnitude of the electromagnetic signal112 can be different than a duration, a frequency, and/or a magnitude ofthe second electromagnetic signal 804. Thus, the generalized system canfacilitate independent and concurrent or sequential localized annealingof at least two Josephson junctions of the at least two of the one ormore qubits (e.g., 104 and 602).

Now, consider FIG. 9. FIG. 9 illustrates a flow diagram of an example,non-limiting computer-implemented method that facilitates annealingmultiple qubits by antenna-based qubit annealing in accordance with oneor more embodiments described herein. That is, FIG. 9 depicts acomputer-implemented method 900 that can comprise thecomputer-implemented method 700 and that can further include a step forannealing multiple qubits/Josephson junctions.

At step 302, as explained, a first radio frequency (RF) emitter can emita first electromagnetic signal onto a first set of one or more capacitorpads of a first Josephson junction on a superconducting qubit chip,wherein the emitting induces an alternating current or voltage in thefirst set of one or more capacitor pads, thereby heating the firstJosephson junction. At step 304, the first RF emitter can anneal thefirst Josephson junction based on the emitting. At step 702, the firstRF emitter can localize the first electromagnetic signal toward thefirst set of one or more capacitor pads of the first Josephson junctionto prevent annealing of a second Josephson junction on thesuperconducting qubit chip by the first electromagnetic signal.

Now, at step 902, a second RF emitter can anneal the second Josephsonjunction by emitting and localizing a second electromagnetic signaltoward a second set of one or more capacitor pads of the secondJosephson junction. Moreover, the emitting and localizing of the secondelectromagnetic signal can occur independently of and concurrently orsequentially with the emitting and localizing of the firstelectromagnetic signal, thereby respectively facilitating independentand concurrent or sequential localized annealing of the first Josephsonjunction and the second Josephson junction. The computer-implementedmethod 900 can be implemented by, for example, the system 800 (and/orthe generalized system) depicted in FIG. 8. Again, such independent(e.g., the durations, frequencies, and/or magnitudes of the first andsecond electromagnetic signals can be independently controllable) andconcurrent annealing of multiple qubits saves time and enables eachqubit to receive a distinct level of annealing, thereby improvingfrequency allocation and reducing quantum cross-talk, therebyconstituting a notable advantage over the prior art.

Now, consider FIG. 10. FIG. 10 illustrates a side-view schematic of anexample, non-limiting system that facilitates antenna-based qubitannealing in accordance with one or more embodiments described herein.

As shown, the qubit annealing system 1000 can comprise a superconductingqubit chip 1002 having a first qubit 1012. As shown in FIG. 10, thefirst qubit 1012 can comprise a first Josephson junction 1004 and afirst set of one or more capacitor pads 1006 (e.g. pads 1006 of acapacitor that is in parallel with the first Josephson junction 1004).The qubit annealing system 1000 can also comprise a first antenna 1008located above the superconducting qubit chip 1002 and that canemit/generate a first electromagnetic wave 1010 onto the first set ofone or more capacitor pads 1006. Substantially as explained above, thefirst electromagnetic wave 1010 can heat the first qubit 1012, therebyannealing the first Josephson junction 1004 of the first qubit 1012.

In one or more embodiments, the first antenna 1008 can be any type ofantenna, signal generator, and/or oscillator that can propagate thefirst electromagnetic wave 1010 through space/air. Moreover, the firstantenna 1008 can be positioned on an emitter chip that is mounted abovethe superconducting qubit chip 1002 (like in FIGS. 1A and 1B). However,in other embodiments, the first antenna 1008 can be mounted onto arobotic manipulator, arm, and/or actuator such that it can bepositioned/moved about the superconducting qubit chip 1002 (e.g., movedin a plane parallel to the plane of the superconducting qubit chip1002). In such case, the first antenna 1008 can be moved such that it issubstantially directly vertically above the first qubit 1012 on thesuperconducting qubit chip 1002, or the first antenna 1008 can be movedsuch that it is substantially directly vertically above another qubit(and/or other circuitry) on the superconducting qubit chip 1002. Instill other embodiments, the first antenna 1008 can be mounted onto arobotic manipulator, arm, and/or actuator such that it can be movedvertically (e.g., moved in the direction normal to the plane of thesuperconducting qubit chip 1002). In such case, the vertical distancebetween the first antenna 1008 and the superconducting qubit chip 1002can be modulated/controlled so as to help modulate/control the amount ofcircuitry (e.g., the number of qubits) on the superconducting qubit chip1002 that receive the first electromagnetic wave 1010. For example,moving the first antenna 1008 farther away from the superconductingqubit chip 1002 can cause more circuitry on the superconducting qubitchip 1002 than just the first qubit 1012 to receive the firstelectromagnetic wave 1010. Conversely, moving the first antenna 1008closer to the superconducting qubit chip 1002 can cause less circuitryon the superconducting qubit chip 1002 to receive the firstelectromagnetic wave 1010. This is because the spanned arc length of awave/signal/beam is directly proportional to the radius/distancetraveled by the wave/signal/beam (e.g., s=r*0). In still one or moreother embodiments, the first antenna 1008 can be stationary.

Those of skill in the art will understand that much of the abovediscussion regarding technical aspects and advantages of FIGS. 1A and 1Bcan be applied to the qubit annealing system 1000 of FIG. 10.

Now, consider FIG. 11. FIG. 11 illustrates a flow diagram of an example,non-limiting computer-implemented method that facilitates antenna-basedqubit annealing in accordance with one or more embodiments describedherein. That is, FIG. 11 depicts the computer-implemented method 1100 ofannealing qubits that can be facilitated, for example, by the systemdiscussed above and/or illustrated in FIG. 10. Those of skill in the artwill appreciate, however, that other systems, devices, and/or apparatuscan be used to implement the computer-implemented method 1100.

At step 1102, a first antenna can emit a first electromagnetic wave ontoa first set of one or more capacitor pads of a superconducting qubitchip, wherein the first electromagnetic wave heats a first Josephsonjunction of a first qubit of the superconducting qubit chip. At step1104, the first antenna can anneal the first Josephson junction of thefirst qubit based on the emitting. In this way, one or more qubits onthe superconducting qubit chip can be independently annealed by acontrollable antenna (e.g., controllable vertical and/or lateralposition of the antenna as well as controllableduration/frequency/magnitude of the generated electromagnetic wave).Those of skill in the art will appreciate that the above discussionregarding electromagnetic signals/waves generating alternatingcurrents/voltages in capacitor pads to heat and anneal qubits/Josephsonjunctions applies to the computer-implemented method 1100. Moreover,much of the discussion regarding technical aspects and advantages ofFIG. 3 above can apply to FIG. 11.

Now, consider FIG. 12. FIG. 12 illustrates a flow diagram of an example,non-limiting computer-implemented method that facilitates adjusting anelectromagnetic wave to achieve a defined level of antenna-based qubitannealing in accordance with one or more embodiments described herein.That is, FIG. 12 depicts a computer-implemented method 1200 that cancomprise the computer-implemented method 1100 and that can furtherinclude a step for adjusting the properties of an electromagnetic waveto correspondingly control the annealing of a targeted qubit.

At step 1102, as described above, a first antenna can emit a firstelectromagnetic wave onto a first set of one or more capacitor pads of asuperconducting qubit chip, wherein the first electromagnetic wave heatsa first Josephson junction of a first qubit of the superconducting qubitchip. At step 1104, also as described above, the first antenna cananneal the first Josephson junction of the first qubit based on theemitting.

Now, at step 1202, the first antenna can adjust at least one of aduration, a frequency, or a magnitude of the first electromagnetic waveto achieve a defined level of the annealing of the first Josephsonjunction of the first qubit. As mentioned above, this can help tofacilitate independent and localized annealing of one or more qubits onthe superconducting qubit chip (e.g., the different qubits can undergovarying levels of annealing depending on their own anneal requirements),thereby improving frequency allocation on the superconducting qubit chipand commensurately reducing quantum cross-talk. Those of skill in theart will appreciate that the above discussion of technical aspects andadvantages in conjunction with FIG. 4 can apply to FIG. 12.

Now, consider FIG. 13. FIG. 13 illustrates a side-view schematic of anexample, non-limiting system that facilitates directed antenna-basedqubit annealing in accordance with one or more embodiments describedherein. As shown, the qubit annealing system 1300 can comprise thesuperconducting qubit chip 1002, a first qubit 1012 having a firstJosephson junction 1004 and a first set of one or more capacitor pads1006, and a first antenna 1008 that can emit/generate a firstelectromagnetic wave 1010.

As shown, the qubit annealing system 1300 can also comprise a secondqubit 1306 on the superconducting qubit chip 1002. The second qubit 1306can have a second set of one or more capacitor pads 1304 and a secondJosephson junction 1302. Moreover, the first antenna 1008 candirect/localize the first electromagnetic wave toward the first set ofone or more capacitor pads 1006 of the first qubit 1012 and away fromthe second set of one or more capacitor pads 1304 of the second qubit1306 to avoid annealing of the second Josephson junction 1302 of thesecond qubit 1306 by the first electromagnetic wave 1010. That is, dueto the directing/localizing, the first electromagnetic wave 1010 can bereceived by the first set of one or more capacitor pads 1006 and not bythe second set of one or more capacitor pads 1304, thereby annealing thefirst Josephson junction 1004 of the first qubit 1012 and not annealingthe second Josephson junction 1302 of the second qubit 1306. Thus, thefirst qubit 1012 can be independently annealed without causing unwantedannealing of the second qubit 1306 and/or other neighboring qubits onthe superconducting qubit chip 1002 (e.g., independent and/or localizedannealing of qubits).

Those of skill in the art will appreciate that much of the abovediscussion regarding technical aspects and advantages (e.g.,localized/directed annealing) in conjunction with FIG. 6 can apply toFIG. 13. So, in one or more embodiments, the first antenna 1008 can be adirectional antenna/transmitter as known in the art such that it canlocalize/direct the first electromagnetic wave 1010 more strongly in aparticular direction (e.g., toward the first set of pads 1006) than inother directions. For example, the first antenna 1008 can comprise anaperture antenna, a parabolic antenna, a helical antenna, a Yagiantenna, a horned antenna, a phase antenna array, and so on. In someembodiments, the first antenna 1008 can be outfitted with electronicactuators such that it can rotate, swivel, and/or otherwise change theprincipal direction in which it directs/localizes the firstelectromagnetic wave 1010.

Now, consider FIG. 14. FIG. 14 illustrates a flow diagram of an example,non-limiting computer-implemented method that facilitates directingantenna-based qubit annealing in accordance with one or more embodimentsdescribed herein. That is, FIG. 14 depicts a computer-implemented method1400 that can comprise the computer-implemented method 1100 and that canfurther include a step for directing/localizing an electromagnetic wavetoward one set of capacitor pads and away from another set.

At step 1102, as explained above, a first antenna can emit a firstelectromagnetic wave onto a first set of one or more capacitor pads of asuperconducting qubit chip, wherein the first electromagnetic wave heatsa first Josephson junction of a first qubit of the superconducting qubitchip. At step 1104, also as explained above, the first antenna cananneal the first Josephson junction of the first qubit based on theemitting.

Now, at step 1402, the first antenna can direct/localize the firstelectromagnetic wave toward the first set of one or more capacitor padsof the first qubit to avoid annealing of a second Josephson junction ofa second qubit on the superconducting qubit chip by the firstelectromagnetic wave. Those of skill in the art will appreciate thatmuch of the discussion of technical aspects and advantages inconjunction with FIG. 7 can apply to FIG. 14. Again, this can help tofacilitate independent and localized annealing of multiple qubits on asuperconducting qubit chip, thereby improving frequency allocation andreducing the likelihood of frequency collisions and/or quantumcross-talk. Such localizing/directing can be accomplished byincorporating a directional antenna component into the first antenna(e.g., an aperture antenna, a parabolic antenna, a helical antenna, aYagi antenna, a horned antenna, a phase antenna array, and so on).

Now, consider FIG. 15. FIG. 15 illustrates a side-view schematic of anexample, non-limiting system that facilitates annealing multiple qubitsby antenna-based qubit annealing in accordance with one or moreembodiments described herein. As shown, the qubit annealing system 1500can comprise the superconducting qubit chip 1002, the first qubit 1012having a first Josephson junction 1004 and a first set of one or morecapacitor pads 1006, the first antenna 1008 that can emit the firstelectromagnetic wave 1010, and the second qubit 1306 having a secondJosephson junction 1302 and a second set of one or more capacitor pads1304.

As shown, the qubit annealing system 1500 can further comprise a secondantenna 1502 located above the superconducting qubit chip 1002. Thesecond antenna 1502 can emit/generate and direct/localize a secondelectromagnetic wave 1504 toward the second set of one or more capacitorpads 1304 of the second qubit 1306, thereby annealing the secondJosephson junction 1302 of the second qubit 1306. Moreover, the secondantenna 1502 can emit/generate and direct/localize the secondelectromagnetic wave 1504 independently of (e.g., can control duration,frequency, and/or magnitude independently of) and concurrently orsequentially with the first antenna 1008 emitting/generating anddirecting/localizing the first electromagnetic wave 1010. This canfacilitate independent and concurrent or sequential localized annealingof the first Josephson junction 1004 of the first qubit 1012 and thesecond Josephson junction 1302 of the second qubit 1306. Those of skillin the art will appreciate that much of the discussion of technicalaspects and advantages regarding FIG. 8 can apply to FIG. 15.

Now, consider FIG. 16. FIG. 16 illustrates a flow diagram of an example,non-limiting computer-implemented method that facilitates annealingmultiple qubits by antenna-based qubit annealing in accordance with oneor more embodiments described herein. That is, FIG. 16 depicts acomputer-implemented method 1600 that can comprise thecomputer-implemented method 1400 and that can further include a step forannealing multiple qubits on a multi-qubit chip.

At step 1102, as described above, a first antenna can emit a firstelectromagnetic wave onto a first set of one or more capacitor pads of asuperconducting qubit chip, wherein the first electromagnetic wave heatsa first Josephson junction of a first qubit of the superconducting qubitchip. At step 1104, also explained above, the first antenna can annealthe first Josephson junction of the first qubit based on the emitting.At step 1402, also as described above, the first antenna candirect/localize the first electromagnetic wave toward the first set ofone or more capacitor pads of the first qubit to avoid annealing of asecond Josephson junction of a second qubit on the superconducting qubitchip by the first electromagnetic wave.

Now, at step 1602, a second antenna can anneal the second Josephsonjunction of the second qubit by emitting/generating anddirecting/localizing a second electromagnetic wave toward a second setof one or more capacitor pads of the second qubit, thereby heating thesecond Josephson junction of the second qubit. Moreover, the emittingand directing of the first electromagnetic wave and the emitting anddirecting of the second electromagnetic wave can occur independently andconcurrently or sequentially, thereby facilitating independent andconcurrent or sequential localized annealing of the first Josephsonjunction of the first qubit and the second Josephson junction of thesecond qubit. Those of skill in the art will appreciate that much of thediscussion of technical aspects and advantages regarding FIG. 9 canapply to FIG. 16.

For simplicity of explanation, the computer-implemented methodologiesare depicted and described as a series of acts. It is to be understoodand appreciated that the subject innovation is not limited by the actsillustrated and/or by the order of acts, for example acts can occur invarious orders and/or concurrently, and with other acts not presentedand described herein. Furthermore, not all illustrated acts can berequired to implement the computer-implemented methodologies inaccordance with the disclosed subject matter. In addition, those skilledin the art will understand and appreciate that the computer-implementedmethodologies could alternatively be represented as a series ofinterrelated states via a state diagram or events. Additionally, itshould be further appreciated that the computer-implementedmethodologies disclosed hereinafter and throughout this specificationare capable of being stored on an article of manufacture to facilitatetransporting and transferring such computer-implemented methodologies tocomputers. The term article of manufacture, as used herein, is intendedto encompass a computer program accessible from any computer-readabledevice or storage media.

In order to provide a context for the various aspects of the disclosedsubject matter, FIG. 17 as well as the following discussion are intendedto provide a general description of a suitable environment in which thevarious aspects of the disclosed subject matter can be implemented. FIG.17 illustrates a block diagram of an example, non-limiting operatingenvironment in which one or more embodiments described herein can befacilitated. Repetitive description of like elements employed in otherembodiments described herein is omitted for sake of brevity. Withreference to FIG. 17, a suitable operating environment 1700 forimplementing various aspects of this disclosure can also include acomputer 1712. The computer 1712 can also include a processing unit1714, a system memory 1716, and a system bus 1718. The system bus 1718couples system components including, but not limited to, the systemmemory 1716 to the processing unit 1714. The processing unit 1714 can beany of various available processors. Dual microprocessors and othermultiprocessor architectures also can be employed as the processing unit1714. The system bus 1718 can be any of several types of busstructure(s) including the memory bus or memory controller, a peripheralbus or external bus, and/or a local bus using any variety of availablebus architectures including, but not limited to, Industrial StandardArchitecture (ISA), Micro-Channel Architecture (MSA), Extended ISA(EISA), Intelligent Drive Electronics (IDE), VESA Local Bus (VLB),Peripheral Component Interconnect (PCI), Card Bus, Universal Serial Bus(USB), Advanced Graphics Port (AGP), Firewire (IEEE 1394), and SmallComputer Systems Interface (SCSI). The system memory 1716 can alsoinclude volatile memory 1720 and nonvolatile memory 1722. The basicinput/output system (BIOS), containing the basic routines to transferinformation between elements within the computer 1712, such as duringstart-up, is stored in nonvolatile memory 1722. By way of illustration,and not limitation, nonvolatile memory 1722 can include read only memory(ROM), programmable ROM (PROM), electrically programmable ROM (EPROM),electrically erasable programmable ROM (EEPROM), flash memory, ornonvolatile random access memory (RAM) (e.g., ferroelectric RAM (FeRAM).Volatile memory 1720 can also include random access memory (RAM), whichacts as external cache memory. By way of illustration and notlimitation, RAM is available in many forms such as static RAM (SRAM),dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM(DDR SDRAM), enhanced SDRAM (ESDRAM), Synchlink DRAM (SLDRAM), directRambus RAM (DRRAM), direct Rambus dynamic RAM (DRDRAM), and Rambusdynamic RAM.

Computer 1712 can also include removable/non-removable,volatile/non-volatile computer storage media. FIG. 17 illustrates, forexample, a disk storage 1724. Disk storage 1724 can also include, but isnot limited to, devices like a magnetic disk drive, floppy disk drive,tape drive, Jaz drive, Zip drive, LS-100 drive, flash memory card, ormemory stick. The disk storage 1724 also can include storage mediaseparately or in combination with other storage media including, but notlimited to, an optical disk drive such as a compact disk ROM device(CD-ROM), CD recordable drive (CD-R Drive), CD rewritable drive (CD-RWDrive) or a digital versatile disk ROM drive (DVD-ROM). To facilitateconnection of the disk storage 1724 to the system bus 1718, a removableor non-removable interface is typically used, such as interface 1726.FIG. 17 also depicts software that acts as an intermediary between usersand the basic computer resources described in the suitable operatingenvironment 1700. Such software can also include, for example, anoperating system 1728. Operating system 1728, which can be stored ondisk storage 1724, acts to control and allocate resources of thecomputer 1712. System applications 1730 take advantage of the managementof resources by operating system 1728 through program modules 1732 andprogram data 1734, e.g., stored either in system memory 1716 or on diskstorage 1724. It is to be appreciated that this disclosure can beimplemented with various operating systems or combinations of operatingsystems. A user enters commands or information into the computer 1712through input device(s) 1736. Input devices 1736 include, but are notlimited to, a pointing device such as a mouse, trackball, stylus, touchpad, keyboard, microphone, joystick, game pad, satellite dish, scanner,TV tuner card, digital camera, digital video camera, web camera, and thelike. These and other input devices connect to the processing unit 1714through the system bus 1718 via interface port(s) 1738. Interfaceport(s) 1738 include, for example, a serial port, a parallel port, agame port, and a universal serial bus (USB). Output device(s) 1740 usesome of the same type of ports as input device(s) 1736. Thus, forexample, a USB port can be used to provide input to computer 1712, andto output information from computer 1712 to an output device 1740.Output adapter 1742 is provided to illustrate that there are some outputdevices 1740 like monitors, speakers, and printers, among other outputdevices 1740, which require special adapters. The output adapters 1742include, by way of illustration and not limitation, video and soundcards that provide a means of connection between the output device 1740and the system bus 1718. It should be noted that other devices and/orsystems of devices provide both input and output capabilities such asremote computer(s) 1744.

Computer 1712 can operate in a networked environment using logicalconnections to one or more remote computers, such as remote computer(s)1744. The remote computer(s) 1744 can be a computer, a server, a router,a network PC, a workstation, a microprocessor based appliance, a peerdevice or other common network node and the like, and typically can alsoinclude many or all of the elements described relative to computer 1712.For purposes of brevity, only a memory storage device 1746 isillustrated with remote computer(s) 1744. Remote computer(s) 1744 islogically connected to computer 1712 through a network interface 1748and then physically connected via communication connection 1750. Networkinterface 1748 encompasses wire and/or wireless communication networkssuch as local-area networks (LAN), wide-area networks (WAN), cellularnetworks, etc. LAN technologies include Fiber Distributed Data Interface(FDDI), Copper Distributed Data Interface (CDDI), Ethernet, Token Ringand the like. WAN technologies include, but are not limited to,point-to-point links, circuit switching networks like IntegratedServices Digital Networks (ISDN) and variations thereon, packetswitching networks, and Digital Subscriber Lines (DSL). Communicationconnection(s) 1750 refers to the hardware/software employed to connectthe network interface 1748 to the system bus 1718. While communicationconnection 1750 is shown for illustrative clarity inside computer 1712,it can also be external to computer 1712. The hardware/software forconnection to the network interface 1748 can also include, for exemplarypurposes only, internal and external technologies such as, modemsincluding regular telephone grade modems, cable modems and DSL modems,ISDN adapters, and Ethernet cards.

The present invention may be a system, a computer-implemented method, anapparatus and/or a computer program product at any possible technicaldetail level of integration. The computer program product can include acomputer readable storage medium (or media) having computer readableprogram instructions thereon for causing a processor to carry outaspects of the present invention. The computer readable storage mediumcan be a tangible device that can retain and store instructions for useby an instruction execution device. The computer readable storage mediumcan be, for example, but is not limited to, an electronic storagedevice, a magnetic storage device, an optical storage device, anelectromagnetic storage device, a semiconductor storage device, or anysuitable combination of the foregoing. A non-exhaustive list of morespecific examples of the computer readable storage medium can alsoinclude the following: a portable computer diskette, a hard disk, arandom access memory (RAM), a read-only memory (ROM), an erasableprogrammable read-only memory (EPROM or Flash memory), a static randomaccess memory (SRAM), a portable compact disc read-only memory (CD-ROM),a digital versatile disk (DVD), a memory stick, a floppy disk, amechanically encoded device such as punch-cards or raised structures ina groove having instructions recorded thereon, and any suitablecombination of the foregoing. A computer readable storage medium, asused herein, is not to be construed as being transitory signals per se,such as radio waves or other freely propagating electromagnetic waves,electromagnetic waves propagating through a waveguide or othertransmission media (e.g., light pulses passing through a fiber-opticcable), or electrical signals transmitted through a wire.

Computer readable program instructions described herein can bedownloaded to respective computing/processing devices from a computerreadable storage medium or to an external computer or external storagedevice via a network, for example, the Internet, a local area network, awide area network and/or a wireless network. The network can comprisecopper transmission cables, optical transmission fibers, wirelesstransmission, routers, firewalls, switches, gateway computers and/oredge servers. A network adapter card or network interface in eachcomputing/processing device receives computer readable programinstructions from the network and forwards the computer readable programinstructions for storage in a computer readable storage medium withinthe respective computing/processing device. Computer readable programinstructions for carrying out operations of the present invention can beassembler instructions, instruction-set-architecture (ISA) instructions,machine instructions, machine dependent instructions, microcode,firmware instructions, state-setting data, configuration data forintegrated circuitry, or either source code or object code written inany combination of one or more programming languages, including anobject oriented programming language such as Smalltalk, C++, or thelike, and procedural programming languages, such as the “C” programminglanguage or similar programming languages. The computer readable programinstructions can execute entirely on the user's computer, partly on theuser's computer, as a stand-alone software package, partly on the user'scomputer and partly on a remote computer or entirely on the remotecomputer or server. In the latter scenario, the remote computer can beconnected to the user's computer through any type of network, includinga local area network (LAN) or a wide area network (WAN), or theconnection can be made to an external computer (for example, through theInternet using an Internet Service Provider). In some embodiments,electronic circuitry including, for example, programmable logiccircuitry, field-programmable gate arrays (FPGA), or programmable logicarrays (PLA) can execute the computer readable program instructions byutilizing state information of the computer readable programinstructions to personalize the electronic circuitry, in order toperform aspects of the present invention.

Aspects of the present invention are described herein with reference toflowchart illustrations and/or block diagrams of methods, apparatus(systems), and computer program products according to embodiments of theinvention. It will be understood that each block of the flowchartillustrations and/or block diagrams, and combinations of blocks in theflowchart illustrations and/or block diagrams, can be implemented bycomputer readable program instructions. These computer readable programinstructions can be provided to a processor of a general purposecomputer, special purpose computer, or other programmable dataprocessing apparatus to produce a machine, such that the instructions,which execute via the processor of the computer or other programmabledata processing apparatus, create means for implementing thefunctions/acts specified in the flowchart and/or block diagram block orblocks. These computer readable program instructions can also be storedin a computer readable storage medium that can direct a computer, aprogrammable data processing apparatus, and/or other devices to functionin a particular manner, such that the computer readable storage mediumhaving instructions stored therein comprises an article of manufactureincluding instructions which implement aspects of the function/actspecified in the flowchart and/or block diagram block or blocks. Thecomputer readable program instructions can also be loaded onto acomputer, other programmable data processing apparatus, or other deviceto cause a series of operational acts to be performed on the computer,other programmable apparatus or other device to produce a computerimplemented process, such that the instructions which execute on thecomputer, other programmable apparatus, or other device implement thefunctions/acts specified in the flowchart and/or block diagram block orblocks.

The flowchart and block diagrams in the Figures illustrate thearchitecture, functionality, and operation of possible implementationsof systems, computer-implemented methods, and computer program productsaccording to various embodiments of the present invention. In thisregard, each block in the flowchart or block diagrams can represent amodule, segment, or portion of instructions, which comprises one or moreexecutable instructions for implementing the specified logicalfunction(s). In some alternative implementations, the functions noted inthe blocks can occur out of the order noted in the Figures. For example,two blocks shown in succession can, in fact, be executed substantiallyconcurrently, or the blocks can sometimes be executed in the reverseorder, depending upon the functionality involved. It will also be notedthat each block of the block diagrams and/or flowchart illustration, andcombinations of blocks in the block diagrams and/or flowchartillustration, can be implemented by special purpose hardware-basedsystems that perform the specified functions or acts or carry outcombinations of special purpose hardware and computer instructions.

While the subject matter has been described above in the general contextof computer-executable instructions of a computer program product thatruns on a computer and/or computers, those skilled in the art willrecognize that this disclosure also can or can be implemented incombination with other program modules. Generally, program modulesinclude routines, programs, components, data structures, etc. thatperform particular tasks and/or implement particular abstract datatypes. Moreover, those skilled in the art will appreciate that theinventive computer-implemented methods can be practiced with othercomputer system configurations, including single-processor ormultiprocessor computer systems, mini-computing devices, mainframecomputers, as well as computers, hand-held computing devices (e.g., PDA,phone), microprocessor-based or programmable consumer or industrialelectronics, and the like. The illustrated aspects can also be practicedin distributed computing environments where tasks are performed byremote processing devices that are linked through a communicationsnetwork. However, some, if not all aspects of this disclosure can bepracticed on stand-alone computers. In a distributed computingenvironment, program modules can be located in both local and remotememory storage devices.

As used in this application, the terms “component,” “system,”“platform,” “interface,” and the like, can refer to and/or can include acomputer-related entity or an entity related to an operational machinewith one or more specific functionalities. The entities disclosed hereincan be either hardware, a combination of hardware and software,software, or software in execution. For example, a component can be, butis not limited to being, a process running on a processor, a processor,an object, an executable, a thread of execution, a program, and/or acomputer. By way of illustration, both an application running on aserver and the server can be a component. One or more components canreside within a process and/or thread of execution and a component canbe localized on one computer and/or distributed between two or morecomputers. In another example, respective components can execute fromvarious computer readable media having various data structures storedthereon. The components can communicate via local and/or remoteprocesses such as in accordance with a signal having one or more datapackets (e.g., data from one component interacting with anothercomponent in a local system, distributed system, and/or across a networksuch as the Internet with other systems via the signal). As anotherexample, a component can be an apparatus with specific functionalityprovided by mechanical parts operated by electric or electroniccircuitry, which is operated by a software or firmware applicationexecuted by a processor. In such a case, the processor can be internalor external to the apparatus and can execute at least a part of thesoftware or firmware application. As yet another example, a componentcan be an apparatus that provides specific functionality throughelectronic components without mechanical parts, wherein the electroniccomponents can include a processor or other means to execute software orfirmware that confers at least in part the functionality of theelectronic components. In an aspect, a component can emulate anelectronic component via a virtual machine, e.g., within a cloudcomputing system.

In addition, the term “or” is intended to mean an inclusive “or” ratherthan an exclusive “or.” That is, unless specified otherwise, or clearfrom context, “X employs A or B” is intended to mean any of the naturalinclusive permutations. That is, if X employs A; X employs B; or Xemploys both A and B, then “X employs A or B” is satisfied under any ofthe foregoing instances. Moreover, articles “a” and “an” as used in thesubject specification and annexed drawings should generally be construedto mean “one or more” unless specified otherwise or clear from contextto be directed to a singular form. As used herein, the terms “example”and/or “exemplary” are utilized to mean serving as an example, instance,or illustration. For the avoidance of doubt, the subject matterdisclosed herein is not limited by such examples. In addition, anyaspect or design described herein as an “example” and/or “exemplary” isnot necessarily to be construed as preferred or advantageous over otheraspects or designs, nor is it meant to preclude equivalent exemplarystructures and techniques known to those of ordinary skill in the art.

As it is employed in the subject specification, the term “processor” canrefer to substantially any computing processing unit or devicecomprising, but not limited to, single-core processors;single-processors with software multithread execution capability;multi-core processors; multi-core processors with software multithreadexecution capability; multi-core processors with hardware multithreadtechnology; parallel platforms; and parallel platforms with distributedshared memory. Additionally, a processor can refer to an integratedcircuit, an application specific integrated circuit (ASIC), a digitalsignal processor (DSP), a field programmable gate array (FPGA), aprogrammable logic controller (PLC), a complex programmable logic device(CPLD), a discrete gate or transistor logic, discrete hardwarecomponents, or any combination thereof designed to perform the functionsdescribed herein. Further, processors can exploit nano-scalearchitectures such as, but not limited to, molecular and quantum-dotbased transistors, switches and gates, in order to optimize space usageor enhance performance of user equipment. A processor can also beimplemented as a combination of computing processing units. In thisdisclosure, terms such as “store,” “storage,” “data store,” datastorage,” “database,” and substantially any other information storagecomponent relevant to operation and functionality of a component areutilized to refer to “memory components,” entities embodied in a“memory,” or components comprising a memory. It is to be appreciatedthat memory and/or memory components described herein can be eithervolatile memory or nonvolatile memory, or can include both volatile andnonvolatile memory. By way of illustration, and not limitation,nonvolatile memory can include read only memory (ROM), programmable ROM(PROM), electrically programmable ROM (EPROM), electrically erasable ROM(EEPROM), flash memory, or nonvolatile random access memory (RAM) (e.g.,ferroelectric RAM (FeRAM). Volatile memory can include RAM, which canact as external cache memory, for example. By way of illustration andnot limitation, RAM is available in many forms such as synchronous RAM(SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rateSDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), Synchlink DRAM (SLDRAM),direct Rambus RAM (DRRAM), direct Rambus dynamic RAM (DRDRAM), andRambus dynamic RAM (RDRAM). Additionally, the disclosed memorycomponents of systems or computer-implemented methods herein areintended to include, without being limited to including, these and anyother suitable types of memory.

What has been described above include mere examples of systems andcomputer-implemented methods. It is, of course, not possible to describeevery conceivable combination of components or computer-implementedmethods for purposes of describing this disclosure, but one of ordinaryskill in the art can recognize that many further combinations andpermutations of this disclosure are possible. Furthermore, to the extentthat the terms “includes,” “has,” “possesses,” and the like are used inthe detailed description, claims, appendices and drawings such terms areintended to be inclusive in a manner similar to the term “comprising” as“comprising” is interpreted when employed as a transitional word in aclaim. The descriptions of the various embodiments have been presentedfor purposes of illustration, but are not intended to be exhaustive orlimited to the embodiments disclosed. Many modifications and variationswill be apparent to those of ordinary skill in the art without departingfrom the scope and spirit of the described embodiments. The terminologyused herein was chosen to best explain the principles of theembodiments, the practical application or technical improvement overtechnologies found in the marketplace, or to enable others of ordinaryskill in the art to understand the embodiments disclosed herein.

The invention claimed is:
 1. A computer-implemented method, comprising:emitting, via a first radio frequency (RF) emitter, a firstelectromagnetic signal onto a first set of one or more capacitor pads ofa first Josephson junction of a superconducting qubit chip, wherein theemitting induces an alternating current or voltage in the first set ofone or more capacitor pads, thereby heating the first Josephsonjunction, localizing, by the first RF emitter, the first electromagneticsignal toward the first set of one or more capacitor pads of the firstJosephson junction to prevent annealing of a second Josephson junctionon the superconducting qubit chip by the first electromagnetic signal;and annealing, by the first RF emitter, the first Josephson junctionbased on the emitting.
 2. The computer-implemented method of claim 1,further comprising: controlling at least one of a duration, a frequency,or a magnitude of the first electromagnetic signal to generate a definedlevel of the annealing of the first Josephson junction.
 3. Thecomputer-implemented method of claim 2, further comprising: ceasing toemit the first electromagnetic signal based on achieving the definedlevel of the annealing of the first Josephson junction.
 4. Thecomputer-implemented method of claim 1, further comprising: annealing,by a second RF emitter, the second Josephson junction by emitting andlocalizing a second electromagnetic signal toward a second set of one ormore capacitor pads of the second Josephson junction, wherein theemitting and localizing of the second electromagnetic signal occurindependently of and concurrently or sequentially with the emitting andlocalizing of the first electromagnetic signal, thereby respectivelyfacilitating independent and concurrent or sequential localizedannealing of the first Josephson junction and the second Josephsonjunction.
 5. The computer-implemented method of claim 4, wherein thefirst RF emitter is positioned above the first set of one or morecapacitor pads of the first Josephson junction and the second RF emitteris positioned above the second set of one or more capacitor pads of thesecond Josephson junction.
 6. The computer-implemented method of claim1, wherein a frequency of the first electromagnetic signal belongs tothe microwave region of the electromagnetic spectrum.